This reference is for Processing 2.0+. If you have a previous version, use the reference included with your software. If you see any errors or have suggestions, please let us know. If you prefer a more technical reference, visit the Processing Javadoc.

Name	alpha()
Examples	noStroke(); color c = color(0, 126, 255, 102); fill(c); rect(15, 15, 35, 70); float value = alpha(c); // Sets 'value' to 102 fill(value); rect(50, 15, 35, 70);
Description	Extracts the alpha value from a color.
Syntax	alpha(rgb)
Parameters	rgb int: any value of the color datatype
Returns	float
Related	red() green() blue() hue() saturation() brightness()